We see the ways in which both documents of the universal magisterium and the teaching documents from local bishops can underpin our catechesis.

During his lengthy pontificate, Pope John Paul II consistently reaffirmed the perennial Christian teaching on the vocation of marriage. In Familiaris Constortio he proclaimed that ‘the family is the first and vital cell of society’[i] and the Catechism, which he promulgated, states that the ‘vocation to marriage is written in the very nature of man and woman’ (CCC 1603).

While the vocation of marriage is clearly defined within Catholic teaching, there exists a pervasive effort to redefine the vocation of marriage as any union between two people, regardless of gender. This debate on so-called ‘same-sex’ marriage is alive and well and shows no signs of diminishing.

The debate began gaining ground during the 20th century and in 2001, the Netherlands became the first country to legalize same-sex marriage—with all the rights and privileges of traditional marriage. Since then, at least six other countries have followed suit and more are on the way.

The following article will highlight some fundamental principles to help explain why marriage cannot be between two people of the same gender. While the Christian faith is rooted in Divine Revelation, much of this article will focus on understanding marriage within the natural moral order. Grace builds on nature;[ii] therefore, understanding the natural origins of marriage will help Christians defend traditional marriage to both Christians and non-Christians alike. We must take seriously St. Peter’s exhortation to, ‘always be prepared to make a defense…for the hope that is in you, yet do it with gentleness and reverence’ (Pet 3:15). It is important that we engage this cultural debate with clarity and charity.